This invention relates to a container from which volatile substances such as insecticides and/or aromatics are evaporated by means of an evaporating device.
Containers for substances evaporated by means of an evaporating apparatus are generally known and commonly used such as containers which are screwed or snapped into a housing of the evaporation apparatus. The container comprises a wick with one end dipping into the volatile substance and an opposite end which extends out of the container. The wick end may also extend into a suitable wick opening of a heating element of the evaporation device for heating. The volatile substance is drawn out of the container by the capillary effect so that the substance is evaporated by the heat from the heating element. The heating element may be in the form of a ceramic block. The substance is able to emerge into the environment through ventilation slits in the housing of the evaporation apparatus. The evaporation device is commonly used for the evaporation of volatile substances, such as insecticides and/or aromatics, in closed rooms of apartments or homes.
One problem with prior evaporation systems is that the volatile substances, particularly in the case of pesticides, can in large quantities be dangerous to the health of humans and in particular of children. For example, when the wick is pulled too far out of a full container a greater quantity of the volatile substance becomes accessible which can be spilled. In addition there is a danger, once a container is empty, that a user might fill up the container with a volatile substance that is flammable, and not suitable for use in the evaporation device. A danger may also exist if an empty container is filled with a insecticide that may not be suitable for evaporation in enclosed spaces due to its high toxicity.
In order to prevent these dangers, a container for volatile substances in an evaporation device has been proposed in U.S. Pat. No. 6,236,807. The proposed container includes a container neck extending from the container having a container opening. A wick retaining insert is inserted into the container opening of the neck which is made as a cylindrical insert sleeve. The sleeve is provided with a holding insert and wick opening for the insertion of the wick. An outside wall of the holding ring insert contacts an inside wall of the container neck at least in some areas. This container furthermore comprises a wick-fixing device by means of which the wick is secured when inserted against being pulled out of the container neck. In practice, the wick-fixing device is provided in accordance with the present invention by a needle inserted radially into the container below the wick retaining insert. The inserted needle penetrates through the wick with two opposite needle ends radially extending from the wick. The wick retaining insert is pressed into the container opening of the container neck by means of a press fit so that if an attempt is made to pull the wick out of the container, the needle engages a lower end of the wick retaining insert providing resistance against the pulling out of the wick. The structure must be designed so that the resistance to the pulling out of the wick meets local ordinances, e.g., a United States ordinance recommending a minimum resistance force of 15 lbs.
However, a problem exists with the prior wick-fixing needle in that the needle is inserted initially through a dry wick made up of a fiber material. When the wick is wet by the volatile substance the wick is softened so that the needle may possibly become loose and detached form the wick. The insertion of the wick is no longer ensured. This is a temporary solution that is not sufficient for the requirements of high quality containers.
It is therefore an object of the present invention to provide a container for volatile substances in which a wick is effectively inserted and retained in the container so that accidental removal of the wick is prevented.